1. Field of the Invention
The present invention relates to a door locking handle assembly of a pull-out and side-swinging lever-action type. The door locking handle assembly is used in a plugboard box and the like. In operation, the retractable handle of the assembly is pulled out of its casing and side-swung through a predetermined angle to permit a catch plate of the assembly to be free from a receiving portion of a stationary frame element.
2. Description of the Prior Art
In a conventional door locking handle assembly of a pull-out and side swinging lever-action type disclosed in Japanese Utility Model Laid-Open No. Hei 3-66369: a cylinder portion is provided in a base-end portion of a casing fixedly mounted on a door; a locking shaft is inserted in the cylindrical portion and rotatably mounted therein but not axially slidable therein; a catch plate is fixedly mounted on a rear-end portion of the looking shaft; a retractable handle folds into a front concave portion of the casing, and has its base-end portion pivoted to a front-end portion of the locking shaft through a first cross pivot; a biasing spring for swingably biasing the retractable handle in its projecting direction on the first cross pivot, the biasing spring being mounted between the locking shaft and the handle; a push button has its leg portion projected from its rear surface, and is provided with a locking hole and an engaging-hook portion in a front-end portion of the leg portion, the push button being connected with a front-end portion of the handle through a second cross pivot; a position-keeping spring disposed between the handle and the push button, and forces the push button to align with the handle along an extension line thereof; a lock unit is fixedly embedded in a lock-receiving portion provided in a front-end portion of the casing; and, a latch element is so arranged as to be interlocked with a rotor of the lock unit, and is biased forward towards the leg portion of the push button by a return spring to have a front-end portion of the latch element engaged with the locking hole so that the handle is locked up in its retracted position.
However, in the conventional door locking handle assembly described above, since the push button is not held in its depressed position when the handle is projected by depressing the push button, there is a fear that the handle is locked up again in its retracted position. Further, when the handle is retracted in the front concave portion of the casing, there is a fear that the push button having been pivoted to the front-end portion of the handle through the cross pivot is over-swung in a direction opposite to the latch element. As a result, when the handle is released from its retracting operation before it is completely retracted in the casing, the locking hole of the front end of the push button fails to engage with the corresponding front-end portion of the latch element so that the handle is swung on the first cross pivot in its projecting; direction under the influence of the biasing spring, which makes it impossible to retract the handle in the casing.